Determination of trace amounts of morphine in human plasma by anodic adsorptive stripping differential pulse voltammetry

New adsorptive anodic differential pulse stripping voltammetry method for the direct determination of morphine at trace levels in human plasma of addicts is proposed.The procedure involves an adsorptive accumulation of morphine on a HMDE,followed by oxidation of adsorbed morphine by voltammetry scan using differential pulse modulation.The optimum conditions for the analysis of morphine are pH 10.5,Eacc of -100 mV（vs.Ag/AgCl）,and tacc of 120 s.The peak current is proportional to the concentration of morphine,and a Linear calibration graph is obtained at 0.01-3.10μg mL^-1.A relative standard deviation of 1.06%（n=5）was obtained,and the limit of detection was 3 ng mL^-1.The capabiLity of the method for the analysis of real samples was evaluated by the determination of morphine in spiked human plasma and addicts human plasma with satisfactory results.     

Simultaneous spectrophotometric determination of cobalt,copper and nickel using 1-（2-thiazolylazo）-2-naphthol by chemometrics methods

The simultaneous determination of cobalt, copper and nickel using 1-（2-thiazolylazo）-2-naphthol （first figure of this article） by spectrophotometric method is a difficult problem in analytical chemistry, due to spectral interferences. By multivariate calibration methods, such as partial least squares （PLS） regression, it is possible to obtain a model adjusted to the concentration values of the mixtures used in the calibration range. Orthogonal signal correction （OSC） is a preprocessing technique used for removing the information unrelated to the target variables based on constrained principal component analysis. OSC is a suitable preprocessing method for PLS calibration of mixtures without loss of prediction capacity using spectrophotometric method. In this study, the calibration model is based on absorption spectra in the 550-750-nm range for 21 different mixtures of cobalt, copper and nickel. Calibration matrices were formed from samples containing 0.05-1.05, 0.05-1.30 and 0.05-0.80 μg·mL^-1 for cobalt, copper and nickel, respectively. The root mean square error of prediction （RMSEP） for cobalt, copper and nickel with OSC and without OSC were 0.007, 0.008, 0.011 and 0.031,0.037, 0.032 μg· mL^-1, respectively. This procedure allows the simultaneous determination of cobalt, copper and nickel in synthetic and real samples and good reliability of the determination was proved.     

Synthesis and Crystal Structure of 3-（ 2- Hydroxybenzly ）-4-（ 4- Hydro xybenzylideneamino ）-（1H） - 1,2,4- Triazole-5-Thione and Its Antibacterial Activities

1 INTRODUCTION 2. 1 Physical measurements Azole derivatives, such as pyrazole, imidazole, All solvent and chemicals were commercial rea- triazole(including benzotriazole), tetrazole and indole, gents and used without further purification. Ele- have extensive biological activities. They have be- mental analyses were performed on a PE 1700 CHN come the central focus of studies for agricultural che- auto elemental analyzer. IR spectra were recorded on micals, medicines, plant growth regul…     

甲硫氨酸-脑啡肽的分子动力学模拟

The conformational properties of Met-enkephalin (Tyr-Gly-Gly-Phe-Met) were investigated by high temperature quenched molecular dynamics simulations in vapor. Each of these selected structures were then analyzed according to their backbone(φ,Ψ) conformational distributions and sorted into 13 families by computing the rms difference between the Cα-C backbone fragments of each residue over all the structures. Selected lowest energy conformations from each of 13 families were thoroughly energy minimized. The results of simulations show that Met-enkephalin is a flexible molecule. It shows a type Ⅰβ-turn, with the Gly2 carbonyl forming a hydrogen bond with the Met5 amino proton and a type Ⅱβ turn, with the Tyr1 amino proton forming a hydrogen bond with the Phe4 carbonyl. The multiple fit were carried out for all of the 13 conformers with morphine(9 atoms on the pharmacophore groups). F2 and F6 were the most similar to morphine. The rms were 0.0504 nm and 0.0726 nm. The results of simulations also show that Tyr amino N corresponds to N on piperidine ring in morphine, Tyr phenol corresponds to the phenol in morphine, the aromatic ring of Phe corresponds to the cyclohexene ring in morphine. The distances between the three pharmacophores, d1 (Tyr N to Tyr OH), d2 (Tyr N to Tyr du1), d3(Tyr N to Phe du2) and d4(Tyr N to Phe du2) were found to be about 0.8, 0.5, 0.7-0.9 and 0.5 nm, respectively, the corresponding, distances of morphine were found to be 0.7697(N18 to O6),0.5143(N18 to du25), 0.3962(N18 to du24)和0.5566(N18 to O15)nm. Therefore, they may be acted on the same receptor. This model should aid in pharmaceutical design of peptide and nonpeptide ligands with opioid.     

An important step towards single-molecule reaction dynamics

正The detection of chemical reaction dynamics at the singlemolecule level is of crucial importance for both scientific studies and industrial applications.As the intrinsic mechanism of a chemical reaction can be uncovered during such a unique detection,it offers an opportunity to understand and control reactions in pharmaceutical engineering and chemical production.However,to date there is still lack of effective method to in-situ study chemical reaction dynamics for small molecule systems in solution[1].     

Switching the emission of di（4-ethoxyphenyl） dibenzofulvene among multiple colors in the solid state

Luminescent materials exhibiting emission switching in the solid state have drawn much attention though there is still no clear design strategy for such materials. In this letter, we reported the crystallization induced emission enhancement （CIEE） of di（4-ethoxyphenyl）dibenzofulvene （1）, and achieved switching its emission among four different colors through modulation of its molecular packing patterns. We have investigated its potential application as optical recording materials. The twisted conformations of CIEE compounds afford morphology dependent emission and facilitate tuning their emission through modulation of molecular packing patterns. Thus we provide a possible design strategy for solid stimulus responsive luminescent materials.     

Synthesis and Crystal Structure of Dichlorodianiline Palladium （Ⅱ） （C6H5NH2）2PdCl2

1 INTRODUCTION Palladium compounds have attracted much attention as a consequence of their application in homogeneous and heterogeneous catalyses[1]. For instance, palladium compounds are the most active catalysts for the carbonylation, such as palladium-catalyzed carbonylation of nitroarenes, aryl halides, alkyne and so on[2～4]. Some dramatic results in the homogeneous catalysis of the reactions of organic compounds, particularly the successful commercial exploitation of the Wacker on…     

The Synthesis of N-Morphine Hapten and Production of Monoclonal Antibody

The drug overdose and addiction is a serious international problem. Therefore developing a rapid, accurate, convenient and cheap method for detecting morphine in urea is useful and necessary, especially for investigation of epidemiology, identification of medical jurisprudence and determination of drug addict etc. There are many compounds that are similar to morphine in chemical structure and tend to have cross-reaction with the anti-morphine antibody. In order to reduce the cross reaction a…     

Synthesis, Crystal Structure and Fluorescent Properties of 1-（4-（Dimethylamino）benzylidene）- 4-（naphthalen- 1-yl） Thiosemicarbazide

1 INTRODUCTION Recently, for the fluorescent properties, Schiff base has been more and more important and widely studied in density optical memories, nonlinear op- tics (NLO), organic light-emitting diodes (OLED), polymer LED and electrogenerated chemilumines- cence (ECL)[1~5]. Thiosemicarbazones are a kind of Schiff bases with thiourea and good ligands easily chelating with transition metal ions. Although they have been studied extensively for a long time due to their chemical and b…     

Synthesis and Crystal Structure of CoCl（ieaa）（C10H7—ieai）（C10H7NH2）

1 INTRODUCTION A number of isonitroso-b-diketones and isonitroso-b-ketoesters such as isonitrosoacetyl- acetone(Hiaa), isonitrosobenzoylacetone(Hiba) and isonitrosoethylacetoacetate (Hieaa) have been employed as reagents in spectrophotometric determination of iron, palladium and ruthenium[1]. Transition metal complexes of such ligands[2] are potential models for metal binding sites in ferroverdin[3]. They were found as dyes and light-absorbing agents for the acceleration of the sol…     

Synthesis of 8-(ω-Chloroalkyl)-dipyrrinones

Dipyrrinones,typically brightyellow compounds with a long axis- polarizedπ- π* excita-tion in the1 4 π- electron- conjugated chromophore,such as xanthobilirubic acid methyl ester(XBRMe) ,are useful building blocks for the syntheses of biologically important tetrapyrrolepigments such as bilirubin(the yellow pigmentof jaundice) [1 ],and they have been extensivelyused as model dipyrrole pigments for the spectroscopic and the photochemical studies of linertetrapyrroles such as bilirubin and bil…     

Synthesis of Novel 1-Alkyl-2-chloro（alkoxy）-1H-indole 3-Carbaldehyde Oximes and Oxime-ethers（esters） Derivatives

A convenient synthesis of 1-alkyl-2-chloro-1H-indole-3-carbaldehyde oximes(5a―5d) and 1-alkyl-2-phenoxy-1H-indole-3-carbaldehyde oximes(6a―6d) from 2-indolone was completed via the Vilsmeier-Haack reac-tion,with N-alkylation and oximation as the key steps.An improved one-pot method for the synthesis of 1-alkyl-2-alkoxy-1H-indole-3-carbaldehyde oximes(7a―7h) from 1-alkyl-2-chloro-1H-indole-3-carbaldehydes(3a―3d) was described.The Williamson reactions and esterification reactions were performed and the oxime-...     

Antibodies as Tailor-Made Chiral Selectors: an Interdisciplinary Approach to Enantiomer Separation and Detection

 It has long been known that the configurational isomers of biologically active compounds, e.g., nutrients, pesticides, and drugs, may exhibit different activities in a chiral environment such as the human body. Although the majority of drugs presently in development are chiral, analytical and preparative methods for the quantitative determination and purification of stereoisomers still lag behind. One reason is that commonly used chiral selectors for the direct resolution of enantiomers are not tailor-made for a specific analyte. The identification of suitable selectors for a particular pair of enantiomers still requires considerable experimentation and is generally demanding with regard to material, time and labor. The rational design of chiral host molecules, therefore, represents a challenge in facilitating enantiomer analysis. In this article, we describe how a combination of techniques ranging from organic synthesis to molecular biology yields antibodies of predetermined specificity and stereoselectivity that can be used as tailor-made chiral selectors for the chromatographic separation of enantiomers and their sensitive detection in immunosensors.     

Synthesis, Crystal Structure and Antibacterial Activity of 1-（（2-Chloroquinolin-3-yl）-methyl）-pyridin-2（1H）-one

On the basis of the interesting structures and biological activities exhibited by several heterocyclic systems possessing the pyridone nucleus such as mappcine and camptothecin, we have planed to design the synthesis, crystal studies and antibacterial activity of the new 1-((2- chloroquinolin-3yl)-methyl)-pyridine-2(1H)-one building block. An X-ray analysis has provided valuable insight into the effect of steric factors on the three-dimensional shape of this compound which serves as a useful advanced intermediate in the synthesis of these biologically active molecules. A multistep synthesis of camptothecin (5) has been designed by retrosynthetic analysis as part of an ongoing program on lead anticancer drug.     

Synthesis and Crystal Structure of DinuclearCadmium Complex [Cd2（phen）4（fca）2]（ClO4）2-（H2O）2

1 INTRODUCTION During the search of molecule-based materials with interesting properties such as catalysis, cla- thration etc., much attention has been focused on the synthesis of one-, two- and three-dimensional extended solids involving cadmium[1], as its d10 configuration permits a wide variety of geometries and coordination numbers. Rigid bridged ligands such as carboxylate groups are frequently used to construct these materials. Therefore, the coordi- nation chemistry of Cd(Ⅱ) ca…     

EFFECT OF IONIC RADII ON UNIT-CELL VOLUMES OF ISOSTRUCTURAL COMPOUNDS

The relation between cell-edges or unit-cell volumes of isostructural compounds and theionic radii has wide applications in crystal chemistry. The authors have proved: (1) For a series of multiple isostructural compounds such as A_mB_n…X_p, when the anionand other cations are fixed, there exists the following relation between the unit-cell volume Vand the radius r_A of a certain cation such as A: V = (a + br_A)(r_X + r_A)~3 (a and b are constants). (2) For binary isostructural compounds A_mX_p, the above relation is reduced to V = k(r_X + r_A)~3 (k is a constant). (3) For binary isostructural compounds the relation between V and r_A~3 is approximatelylinear, and for multiple compounds, it is often curvilinear but still approximately linear whenthe variation of r_A is slight. As another approximation, a linear relation also exists betweenV and r_A for isostructural compounds. (4) The relation of ce1l-edge a vs. r_A is linear for binary isostructural compounds. Butno such a good linear relation exists fo     

Highly Efficient Regio- and Stereoselective Synthesis of β-（1 →6）-Branched β-（1 →3）-Linked Glucohexaose and Its Analogue

A β-（1→）6）-branched β-（1→）3）-linked glucohexaose （1） and its lauryl glycoside （2）, present in many biologically active polysaccharides from traditional herbal medicines such as Ganoderma lucidum, Schizophyllum commune and Lentinus edodes, were highly efficiently synthesized. Coupling of 2,3,4,6-tetra-O-benzoyl-β-D-glucopyranosyl- （1--）3）-2-O-benzoyl-4,6-O-benzylidene-a-D-glucopyranosyl trichloroacetimidate （7） with 3,6-branched acceptors 8 and 12 gave β-（1→）3）-linked pentasaccharides （9） and （13）, then via simple chemical transformation 4＇,6＇-OH pentasaccharide acceptors 10 and 14 were obtained. Regio- and stereoselective coupling of 3 with 10 and 14 gave β-（1→）3）-linked hexasaccharides （11） and （15） as the major products. Deprotection of 11 and 15 provided the target sugar 1 and 2. Thus, a new method for the preparation of this kind of compounds was developed.     

1-（（12-Bromododecyl）oxy）-4-（（4-（4-pentylcyclohexyl） phenyl）ethynyl） benzene：Liquid crystal with aggregation-induced emission characteristics

The luminescent liquid crystals （LLCs） are expected to solve the conflicts between the aggregation caused quenching and the requirement of aggregation or self-organization for LCs. Herein, we developed a new strategy of applying aggregation-induced emission （AIE） phenomenon to the molecular design of LCs towards LLCs. In this report, a calamitic liquid crystal based on tolane with AIE characteristics was successfully synthesized and the chemical structure was characterized by 1H, 13C NMR, and matrix-assisted laser desorption/ionization time-of-flight （MALDI-TOF） high-resolution mass spectra. The fluorescence behavior was studied by fluorescence spectroscopy and the liquid crystal phase behaviors were investigated by differential scanning calorimetry （DSC）, polarized optical microscopy （POM）. The crystal structure was obtained by X-ray diffraction crystallography with P1 space group. Results demonstrated that the sample was AIE active and the LC phases sequence during cooling was nematic, smectic C and smectic B phase.     

Molecularly imprinted polymers for highly sensitive detection of morphine using surface plasmon resonance spectroscopy

Molecular imprinting technology is applied in surface plasmon resonance spectroscopy for highly sensitive and selective detection of morphine（MO）.As SPR-based sensor of MO,the preparation of molecular imprinted polymer is as follows: methacryhc acids（MAA）,ethylene glycol dimethacrylate（EGDMA）,azodiisobutyronitrile（AIBN） were used as functional monomer,cross-linker and initiator,respectively.The experiment results showed that morphine imprinted polymer had the performance of high sensitivity and specificity,i.e.the relative signal of SPR response was proportional to the concentration of morphine in acetonitrile in the range of 10^-9mol/L to 10^-6mol/L（1 ppb-1 ppm） with LOD of 10^-10mol/L,and MO was distinguished from its analogs,such as codeine.     

Synthesis and Crystal Structure of 3,5-Diphenyl- 1,2- di（4- chlorophenyl）pyrrole

1 INTRODUCTION The pyrrole ring constitutes a basic heteroaro- matic structure. It is a vital building block for the construction of porphyrins and alkloids[1]. Several substituted pyrroles have potential applications as fungicides and bactericides and as active compo- nents of nonsteroidal anti-inflammatory drugs inhi- biting human cyclooxygenase[2, 3]. Besides the clas- sical Knorr’s method, there are a number of poten- tially useful methods for the synthesis of pyrrole he- terocyclic …